Salmon Poisoning (Fish Flu) is passed by the Nanophyetus salmonicola fluke present in raw fish (especially Salmon). This fluke sometimes harbors a toxic rickettsial organism inside called Neorickettsia helminthoeca. It is the rickettsial organism that is harmful and potentially fatal to the canid family which includes dogs, foxes, coyotes, and wolves. Salmon poisoning occurs most commonly west of the Cascade mountain.
Symptoms, which usually appear within six days after eating the raw fish include: vomiting, lack of appetite, fever (up to 104 degrees F), diarrhea, weakness, extremely swollen lymph nodes and dehydration. If left untreated death usually occurs within two weeks of eating the infected fish.
If you think your animal may have gotten into fish or it wanders the neighborhood and may have gotten into a trash can with fish in it, please tell your veterinarian.
Diagnosis is through symptoms and by doing a direct fecal smear of the golden looking diarrhea and seeing the golden-colored operculated eggs in the fresh stool (if we’re lucky). A needle biopsy of the lymph node can also reveal the rickettsial organism.
Treatment includes antibiotics (usually tetracycline), steroids and a tape wormer (I use Cestex. Often symptoms and extensive treatment can be abated if the tape wormer is given within 24 hours of ingesting the fish. Dogs respond very quickly with treatment—usually in only a couple days.
Prevention: Keep dogs away from raw fish, fish cleanings, and fish skin. And it’s nice to have a dose of tape wormer with you if you are headed into the woods for a week-long fishing trip with your dog!
Helpful Links and Reference:
- Info on Salmon Disease: https://www.vetmed.wsu.edu/ClientED/salmon.asp
- Great Reference page: https://www.acpmedicine.com/acp/chapters/ch0735.htm
- Article on Salmon disease poisoning: https://www.merckvetmanual.com/mvm/index.jsp?cfile=htm/bc/57305.htm